Cesium carbonate → 4-{3-[7-tert-butylcarbamoyl-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-5-difluoromethoxy-indazol-1-yl}-butyric acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A microwave vial was charged with 2-(5-difluoromethoxy-1H-indazol-3-yl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid tert-butylamide (100 mg, 0.19 mmol), methyl 4-bromobutanoate (69 mg, 0.38 mmol), cesium carbonate (184 mg, 0.57 mmol) and DMF (0.85 ml). The vial was flushed with argon, sealed and heated in a microwave reactor at 100° C. for 2 h. The reaction was quenched with water and extracted with diethyl ether (2×). The combined organic layers were washed twice with water and once with brine then dried over sodium sulfate, filtered and concentrated. The residue was chromatographed over 12 g silica gel with EtOAc/hexanes (gradient: 0-30% EtOAc) to afford 99 mg (83%) of 4-{3-[7-tert-butylcarbamoyl-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-5-difluoromethoxy-indazol-1-yl}-butyric acid methyl ester as a light yellow solid.

Provenance & Evidence